Publikasjoner
NIBIOs ansatte publiserer flere hundre vitenskapelige artikler og forskningsrapporter hvert år. Her finner du referanser og lenker til publikasjoner og andre forsknings- og formidlingsaktiviteter. Samlingen oppdateres løpende med både nytt og historisk materiale. For mer informasjon om NIBIOs publikasjoner, besøk NIBIOs bibliotek.
2007
Forfattere
Trygve S. Aamlid Gunvald Henning JonassenSammendrag
Field trials comparing various combinations of 0, 30 or 60 kg N ha-1 in autumn (September) and/or spring (April) to seed crops of common bent (syn. browntop, US: colonial bentgrass, Agrostis capillaris L.) "Leikvin" (main use: long-lasting pastures and utility turf) and "Nor" (main use: lawns and golf course fairways) were carried out on silt loam soils at Landvik, south-east Norway (58°N) from 1989 to 1994. One trial per cultivar was established in 1989, 1990 and 1991, each trial being harvested for three years. On average, for nine harvests and nine N treatments, "Leikvin" and "Nor" gave seed yields of 276 and 128 kg ha-1, respectively. Seed yields of "Leikvin" increased with increasing N rate up to 60 kg N ha-1 in autumn and 30 kg N ha-1 in spring; no interaction between autumn and spring N rate could be detected in this cultivar. In "Nor", a significant autumn x spring rate interaction indicated a linear seed yield response to N in spring on plots that had received 60 kg N ha-1 in autumn, but a diminishing response to N in spring on plots that had received 0 or 30 kg N ha-1 in autumn; the highest seed yield was produced with autumn + spring applications of 60 + 60 kg N ha-1 in this lawn cultivar. While panicle number and seed number per panicle were equally important for seed yield in "Leikvin", panicle number had the stronger impact on seed yield in"Nor". Seed crops of "Leikvin" were generally taller and more susceptible to lodging than seed crops of "Nor". Year-to-year variations in seed yield level and optimal N regime were less related to crop age than to weather conditions and seed crop management. Given the present prices for fertilizer and seed, it is concluded that Norwegian seed crops of common bent should receive 50-60 kg N ha-1 in autumn regardless of cultivar. Economically optimal N rates in spring are 30 and 60 kg N ha-1 to "Leikvin" and "Nor", respectively.
Sammendrag
Empirical evidence that the N dissipation from dairy production depends tightly on the segregation of animals from plant production is provided
Sammendrag
Furfurylated wood (wood modified by furfuryl alcohol) has over the last years gained marked shares from both tropical wood and conventional preservative treated wood and this has, in turn, generated several research projects concerning process development. The impregnation of spruce is well known from literature to be a difficult task. Furthermore, the sapwood of Scandinavian grown Scots pine is also known to be difficult to fully impregnate from time to time. The primary objective of the study was to evaluate whether the Oscillating Pressure Method (OPM) could be used to impregnate green and dry Norway spruce wood (Picea abies) with a Furfuryl alcohol (FA) - mixture. The secondary objective of the study was to evaluate if OPM could improve the penetration of FA in Scots pine (Pinus sylvestris) as compared to conventional full cell (Bethell) treatment. Impregnation tests were carried out on boards and planks as well as 300 mm and 500 mm clear wood samples. Samples were removed for MC measurement and the initial weight of the test samples was determined. Four different impregnation schemes were tested. The results indicate that Norway spruce can be impregnated by the OPM method to produce a protective shell of treated wood around a core of untreated wood. The penetration in Spruce showed great variation between different boards and between different parts of the individual boards. This is in part expected, but can also be caused by uncontrolled pre drying of the test material which was stacked uncovered after sawing. For Scots pine, the OPM improved the penetration of both sapwood and, to some extent, the outer heartwood.
Forfattere
Roar LågbuSammendrag
En videreføring av dagens fremdrift i jordsmonnkartleggingen innebærer at vi først om 40 – 50 år vil ha kartlagt alt jordsmonnarealet i Norge. Ved å gjennomføre utvalgskartlegging i regionene der vi mangler data får vi mulighet til å generere jordsmonnstatistikk som kan være en nyttig informasjonskilde inntil jordsmonnkart foreligger for hele landet. Bruk av Lucas-flatene i et rutenett på 18x18 km, og et fortettet nett på 9x9 km, er egnet til dette. For å se nærmere på kvaliteten til utvalgsstatistikk basert på Lucas-flatene, er statistikk basert på utvalgskartlegging sammenliknet med statistikk basert på fullstendig jordsmonnkartlegging. Oslo, Akershus, Vestfold og Østfold er valgt som studieområde siden vi har fullstendig jordsmonnkartlegging for disse fylkene. Generelt er avviket mellom estimert areal basert på utvalgskartlegging og faktisk areal basert på fullstendig jordsmonnkartlegging større i 18x18-rutenettet en i 9x9- rutenettet for de seks jordsmonnegenskapene vi har studert. For totalt jordsmonnareal er imidlertid overraskende nok avviket i arealtallet fra 18x18 km rutenettet mindre enn arealtallet generert fra 9x9-rutenettet. Dette er et eksempel på at utvalgskartlegging alltid har en grad av usikkerhet knyttet til seg, på grunn av den tilfeldigheten det er hvor flatene faller geografisk. Likevel er det forekomsten og den geografiske spreningen av en egenskapsklasse som er de to faktorene som i hovedsak påvirker avviket mellom statistikken basert på utvalgskartlegging og statistikken basert på fullstendig jordsmonnkart. Har en egenskapsklasse liten forekomst og er geografisk konsentrert innenfor studieområdet innebærer det stor grad av sannsynelighet for underrepresentativitet. Har en egenskapsklasse stor forekomst og er geografisk konsentrert er det sannsynelighet for overrepresentativitet. Er en egenskapsklasse geografisk spredt er det sannsynelighet for god representativitet uavhengig av om egenskapsklassen har liten eller stor forekomst.
Forfattere
Tor Håkon SivertsenSammendrag
A few ideas connected to the scope of scientific work in agronomy and agro meteorology and the scope of the scientific principle is first outlined. Then the concepts of `sustainability" and `sustainable agriculture" is presented, and the content of different definitions of these concepts is discussed. General ideas of using quantitative parameters, indices, to measure sustainability is presented. Then different ways of defining indices is discussed.A concept connected to `subsistence farmimg" called `tiny orchard" is presented and discussed, and the possible use of this concept `tiny orchard" as a referenc system for measuring and definig `sustainable agriculture" is discussed. The actual life cycle of a commercial agricultural product , an apple to be consumed fresh, is outlined; and this is compared to what is happening in a `tiny orchard" with and apple on an apple tree. Some importantant cycles connected to sustainable agriculture is mentioned, the fresh water cycle and the cycles of nitrogen and phosphorous. The following idea is discussed:"The idea of changing the focus in agricultural production from maximizing the crop yield to keeping the ecolological system of the farming and the local area sound and in order". Man is an organism like other organisms. He ought to take care of his surroundings and the other species, to take care of a ttallity of biological systems on the Eatth. probaly no god or gods will take care of him if does not succed in doeng this.The content of the concepts of adaption and mitigation connected to clobal change is also finally mentioned. References and biblography: Leane, M., 2005, The quest for an Environmental Metric: gazing at weather systems, a ground-breaking scientist spawned on ecological accounting standard the Wall Street might one day embrace ( http:// www.cfo/printable/article.cfn/530007?f=options), CFO Publishing Maine, T., 2005, Towards a Metric of Sustanability ( http://www.isoconference.org.au/ papers/ Maine.pdf), CSIRO Publish Jain, R., 2005, Sustainability metrics, specific indicators and preference index (http://www.springerlink.com/media/h4d4779uuq0yynfhktb6/contributions/t/2/2/5/t22524055312t88.pdf), Clean Techn. Environ. Polocy /:71-72
Sammendrag
I Haldenvassdraget og Morsavassdraget er det sterkt fokus på redusert jordarbeiding for å redusere erosjon og fosforavrenning. Jordartene i nedbørfeltene er dominert av marine avsetninger med siltig mellomleire, siltig lettleire og sand. Jorda langs Morsavassdraget er noe lettere enn jorda i Haldenvassdraget. Jordegenskapene har betydning for de agronomiske mulighetene for og miljøeffektene av redusert jordarbeiding. Rent agronomisk eller dyrkingsmessig gir endring av normal praksis for jordarbeiding en del utfordringer. Noen av disse utfordringene som bonden ser, er reelle, men ikke nødvendigvis alle. Vårpløying er et tiltak som ikke krever vesentlige endringer på maskinparken, men kunnskapen om smuldring, laglighet og bearbeidingsdybde blir mer avgjørende enn ved den tradisjonelle høstpløyinga. Vårpløying er et interessant alternativ for jordarbeiding fordi det har stor effekt på erosjon samtidig som ugraset kontrolleres godt. I forsøk har høstpløying gitt avlinger på 488, vårpløying 492 og vårharving 510 kg/daa på siltig mellomleire i Ås. Generelt er det for vårharving og direktesåing en viss risiko for noe avlingsnedgang over tid. I praksis forventer vi at direktesåing er noe mer utsatt for reduserte avlinger enn vårharving selv om dette ikke er like synlig i de ulike langvarige forsøkene. I forsøk med direktesåing var det ingen forhold som tydet på at det er nødvendig å pløye for å «kvitte» seg med halmen der jorda ble direktesådd i mange år etter hverandre uten å fjerne halmen. Halmen kan føre til spirehemming på grunn av stoffer som skilles ut ved nedbrytning av halmen og på grunn av immobilisering av nitrogen. Dessuten kan halmen overføre plantesykdommer fra et år til et annet. Det er generelt små forskjeller i jordstruktur, målt som porevolum og jordtetthet. Det er imidlertid gjennomgående at en finner noe større vannlagringsevne i jorda, men noe mindre luft. Fastheten i jorda øker noe. Dette behøver ikke være negativt da dette tilsier at jordas bæreevne øker. Redusert jordarbeiding har påvirket innholdet av organisk materiale i jorda mer enn nedmolding av halm. […]
Sammendrag
In Norway, Nordmann (Abies nordmanniana) and subalpine fir (A. lasiocarpa) are the dominant Christmas tree species and Noble fir (A. procera) the dominant species for bough production. In the spring of 2005 a survey was undertaken to determine the presence of fungi on seeds of these three plant species. Twelve seed samples were tested; five from Nordmann fir, four from subalpine fir and three from Noble fir. The test included seeds produced in Austria (Nordmann fir), Canada (subalpine fir), Georgia (Nordmann fir), Norway (Noble and subalpine fir) and Russia (Nordmann fir). The testing was done in a certified seed laboratory in Norway. One hundred seeds per sample were pre-treated in 1 % NaOCl and plated on potato dextrose agar (PDA), and 100 seeds per sample were pre-treated in H2O2 and plated on water agar (WA). The PDA Petri dishes were incubated for 5 to 7 days at 20 + 2 ºC and the WA Petri dishes for 15 to 19 days at 15 + 2 ºC, both under alternating 12 h NUV-light and 12 h darkness. To date not all of the fungi have been identified, but fungi from several genera have been found: Alternaria, Anthostomella, Aspergillus, Aureobasidium, Botrytis, Caloscypha, Cephalosporium, Chaetomium, Cladosporium, Dictyopolyschema, Epicoccum, Fusarium, Mucor, Penicillium, Phoma, Rhizopus, Trichoderma, and Trichothecium. Caloscypha was only found on one subalpine fir seedlot from Canada and Anthostomella on one subalpine fir seed from Norway. All the other fungi were more commonly found in all the samples. Fusarium species are well known to cause damping off in nurseries, but are not reported to cause problems in production fields. Species of Alternaria, Phoma, Botrytis and Trichothecium can damage seedlings. Anthostomella conorum is reported on cone scales of pine (Pinus spp.), but is not described as pathogenic. Aureobasidium is described as a saprophytic or weakly parasitic cosmopolitan fungal genus. Aureobasidium sp. is commonly found in Norway on buds of subalpine fir which fail to open in spring, and it will therefore be included in a pathogenicity test.
Forfattere
Trygve S. Aamlid Larsbo Mats Nick JarvisSammendrag
Fungi, especially those causing winter diseases, are major problems on golf course putting greens in Scandinavia. Although diseases can be prevented by cultivar selection and optimal maintenance, it is difficult to manage creeping bentgrass (Agrostis stolonifera) and annual bluegrass (Poa annua) greens totally without fungicides. Previous research showed that three commonly used fungicides; iprodione, azoxystrobin, and propiconazole, are liable to leaching when used on sand-based putting greens. One possible reason for this liability is the development of hydrophobic layers or spots causing water to percolate in fingers instead of uniformly through the root zone. The objective of this project was to study the effect of organic amendment and surfactant on turfgrass quality, hydrophobicity and fungicide leaching from a USGA putting green. An experiment was conducted from May 2006 till May 2007 on a three year old experimental green seeded to creeping bentgrass `Penn A-4" in the field lysimeter facility at Bioforsk Øst Landvik, SE Norway (Fig. 1). The experimental plan included two root zone compositions (straight sand vs the same sand amended with 2.3 % (w/w) garden compost (`Green Mix")); two surfactant treatments (no surfactant vs `Primer 604", 19 L/ha applied at monthly intervals from May to September 2006); and two fungicides, Rovral 750 (iprodione 1.5 kg a.i./ha) and Amistar Duo (azoxystrobin + propiconazole, 600 + 375 g a.i./ha), sprayed on three occasions; June, July and October 2006) in factorial combination. Turfgrass quality and disease occurrence, infiltration of water vs ethanol, water droplet penetration time, and spatial variability in soil water content was determined at regular time intervals. Fungicides in leaching water were analyzed 2 - 3 weeks after each application and after snow melt / soil thaw in spring 2007. Regular application of `Primer 604" reduced dry spot occurrence and improved turfgrass quality during the summer months, especially on straight sand plots. This improvement was associated with increased water infiltration rates and a reduction in the spatial variability in soil water content at 4 - 10 cm depth, suggesting that hydrophobicity extended deeper in the profile than the 14 - 19 mm thatch/mat layer. However, despite pesticide application, `Primer 604" also increased snow mold (Microdochioum nivale and Typhula spp.) incidence in spring 2007, probably because of a significant increase in the mean soil water content in the thatch"mat layer during the unusually mild and wet winter months (mean temperature / total precipitation from November 2006 to March 2007 was 3.5°C / 751 mm compared with 30 yr normal of 0.2°C / 516 mm). Leaching of fungicides from root zones with 2.3 % organic matter was always negligible, but, regular use of `Primer 604" on rootzones reduced the total leaching of iprodione, azoxystrobin, and propiconazole from straight sand with 60, 63 and 80 %, respectively. In conclusion, `Primer 604" offers many advantages on straight sand rootzones, but there is also a need for new surfactants that retain less water in the thatch layer during the winter months.
Sammendrag
available, especially in Norway. The objective of the present research was to estimate C losses from cultivated peatlands in West Norway by three independent methods: 1) long-term monitoring of subsidence rates, 2) changes in ash contents, and 3) soil CO2 flux measurements. Subsidence of cultivated peat soils averaged about 2.5 cm y-1. We estimated that peat loss and compaction were respectively responsible for 38% and 62% of the total subsidence during a 25-year period after drainage. Based on this estimate the corresponding C loss equals 0.80 kg C m-2 yr-1. The observed increase in mineral concentration of the topsoil of cultivated peat is proportional to their C loss, providing no mineral particles other than lime and fertilizers are added to the soil. Using this novel approach across 11 sites, we estimated a mean C loss of 0.86 kg C m-2 y-1. Soil CO2 flux measurements, corrected for autotrophic respiration, yielded a C loss estimate from cultivated peat soils of 0.60 kg C m-2 yr-1. The three methods yielded fairly similar estimates of C losses from Norwegian cultivated peatlands. Cultivated peatlands in Norway cover an estimated 63 000 ha. Total annual C losses from peat degradation were estimated to range between 1.8 and 2 million tons CO2 y-1, which equals about 3-4 % of total anthropogenic greenhouse gas emissions from Norway.
Forfattere
Bernt HoelSammendrag
I årene 2003-2005 ble det gjennomført forsøk med gjødslingstrategier til bygg (30 felt) og havre (16 felt) på Østlandet og i Midt-Norge. Med riktig valg av delgjødslingsstrategi, viser resultatene at en ofte kan oppnå en viss avlingsgevinst for delt gjødsling til bygg. I havre tyder resultatene på at potensialet for meravling ved delt gjødsling er mindre, men det er realistisk å kunne opprettholde avlingsnivået. Mange korndyrkere ønsker av ulike årsaker å benytte delt gjødsling til bygg og havre. Med en slik strategi kan dyrkeren ved vårgjødsling gi en gjødselmengde tilpasset en meget forsiktig avlingsforventning, ved delgjødslingstidspunktet kan bestandets potensial vurderes og gjødselmengden tilpasses dette. Denne justeringsmuligheten representerer en potensiell miljømessig og økonomisk gevinst. Både på leirjord og lettere jord kan gjødslinga ved såing være svak (5 kg N pr. daa ble prøvd i disse forsøkene), forutsatt at det følges opp med tidlig delgjødsling. Dersom en ved svak vårgjødsling venter med delgjødsling til begynnende stråstrekning risikerer en imidlertid et betydelig avlingstap, særlig på lett jord. En strategi som gir mer fleksibilitet omkring valget av delgjødslingstidspunkt er ei mer moderat vårgjødsling (8 kg N pr. daa i disse forsøkene). På leirjord kan en da anbefale å vente med delgjødsling til begynnende stråstrekning. En risikerer heller ikke på lettere jord noe stort avlingstap ved å utsette delgjødslinga til dette vekststadiet, dersom vårgjødslinga er moderat.